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PubMed2001

Anonymous reporting of HIV infection: an evaluation of the HIV/AIDS surveillance system in Norway 1983-2000.

Several European countries are considering implementing surveillance systems for HIV infection, but questions remain regarding patient confidentiality. The population-based HIV/AIDS surveillance system in Norway integrates anonymous HIV case reports from laboratories and clinicians and named AIDS case reports. This evaluation includes a description of the system, evidence of system attributes, estimation of resources for system operations, and documentation of the system's usefulness. HIV case reports provide a far better picture of the epidemic than AIDS reports. The median delay between positive HIV test and reporting was 30 days (interquartile range 18-49 days). Completeness of demographic and epidemiologic information in the surveillance database ranges from 60 to 100%. Information on pre-AIDS mortality and emigration is incomplete. The system cost euro 25,200 in 1999. Results are published every week and used for planning of health care and prevention. We conclude that the Norwegian surveillance system with anonymous reporting of HIV cases is simple, inexpensive and flexible, and capable of providing a representative and timely overview that guides prevention. The system fulfils its objectives while respecting confidentiality and adhering to ethical principles. A similar system may be considered in other countries.

Acquired Immunodeficiency Syndrome↗
PubMed1995

Evaluation of infection control measures in preventing the nosocomial transmission of multidrug-resistant Mycobacterium tuberculosis in a New York City hospital.

OBJECTIVE: To evaluate the efficacy of Centers for Disease Control and Prevention (CDC)-recommended infection control measures implemented in response to an outbreak of multidrug-resistant (MDR) tuberculosis (TB). DESIGN: Retrospective cohort studies of acquired immunodeficiency syndrome (AIDS) patients and healthcare workers. The study period (January 1989 through September 1992) was divided into period I, before changes in infection control; period II, after aggressive use of administrative controls (eg, rapid placement of TB patients or suspected TB patients in single-patient rooms); and period III, while engineering changes were made (eg, improving ventilation in TB isolation rooms). SETTING: A New York City hospital that was the site of one of the first reported outbreaks of MDR-TB among AIDS patients in the United States. PARTICIPANTS: All AIDS patients admitted during periods I and II. Healthcare workers on nine inpatient units with TB patients and six without TB patients. RESULTS: The epidemic (38 patients) waned during period II and only one MDR-TB patient presented during period III. The MDR-TB attack rate among AIDS patients hospitalized on the same ward on the same days as an infectious MDR-TB patient was 8.8% (19 of 216) during period I, decreasing to 2.6% (5 of 193; P = 0.01) during period II. In a small group of healthcare workers with tuberculin skin test data, conversions during periods II through III were higher on wards with than without TB patients (5 of 29 versus 0 of 15; P = 0.15), although the difference was not statistically significant. CONCLUSIONS: Transmission of MDR-TB among AIDS patients decreased markedly after enforcement of readily implementable administrative measures, ending the outbreak. However, tuberculin skin-test conversions among healthcare workers may not have been prevented by these measures. CDC guidelines for prevention of nosocomial transmission of TB should be implemented fully at all US hospitals.

AIDS-Related Opportunistic Infections↗
PubMed1983

Ceftazidime treatment in intensive care patients.

In the intensive care unit 39 patients were treated with ceftazidime for 52 infections (38 broncho-pulmonary infections, 4 intra-abdominal abscesses, 6 septicaemia, 3 urinary tract infections and 1 mediastinitis). All patients were ventilated mechanically. Three patients (6 infections) were not evaluable. In all cases except one, ceftazidime was administered after clinical failure of other antibiotics, including aminoglycosides. Ceftazidime was successful in 32 out of 46 evaluable infections (70%), while its success rate in infections previously treated with aminoglycosides (alone or in combination with cephalothin or cefotaxime) was 78% (21 out of 27 infections). In the higher dosage group (2000 mg tds) the drug was successful in 20 out of 23 infections compared with 12 out of 21 infections in the lower dosage group (1000 mg tds). Altogether 69 bacterial strains were cultured including 30 strains of Pseudomonas aeruginosa. Ceftazidime was clinically successful against 49 and 25 strains, respectively (71 and 83%, respectively). Bacterial overgrowth was present in 13 patients (14 strains) with broncho-pulmonary infections, but in only 7 was a change to another antibiotic required. Elevation of liver function enzymes was recorded in 4 patients, but it was not necessary to stop ceftazidime prematurely. This drug is an effective and relatively safe agent for the treatment of serious infections caused by Gram-negative bacilli including Pseudomonas aeruginosa in critically ill patients.

Abscess↗
PubMed1996

Macrophages and CD4+ T lymphocytes from two multiply exposed, uninfected individuals resist infection with primary non-syncytium-inducing isolates of human immunodeficiency virus type 1.

Despite multiple, high-risk sexual exposures, some individuals remain uninfected with human immunodeficiency virus type 1 (HIV-1). CD4+ lymphocytes from these individuals are less susceptible to infection in vitro with some strains of HIV-1, suggesting that the phenotype of the virus may influence its ability to interact with certain CD4+ cells. In the present study, we examined the susceptibility of CD4+ T lymphocytes and macrophages from two exposed uninfected individuals (EU2 and EU3) to infection with a panel of biologically cloned isolates of HIV-1 having either a non-syncytium-inducing (NSI) or a syncytium-inducing (SI) phenotype. Our results indicate that CD4+ T lymphocytes from EU2 and EU3 are resistant to infection with NSI isolates of HIV-1 but are susceptible to infection with primary SI isolates. In addition, we found that macrophages from EU2 and EU3 are resistant to infection with both NSI and SI isolates. The latter finding was confirmed by using several uncloned NSI and SI isolates obtained from patients during acute HIV-1 infection. In further experiments, env clones encoding glycoproteins characteristic of NSI or SI viruses were used in single-cycle infectivity assays to evaluate infection of CD4+ lymphocytes and macrophages from EU2 and EU3. Consistent with our previous results, we found that macrophages from these individuals are resistant to infection with NSI and SI env-pseudotyped viruses, while CD4+ T lymphocytes are resistant to NSI, but not SI, pseudotyped viruses. Overall, our results demonstrate that CD4+ cells from two exposed uninfected individuals resist infection in vitro with primary, macrophage-tropic, NSI isolates of HIV-1, which is the predominant viral phenotype found following HIV-1 transmission. Furthermore, infection with NSI isolates was blocked in both CD4+ T lymphocytes and macrophages from these individuals, suggesting that there may be a common mechanism for resistance in both cell types.

CD4-Positive T-Lymphocytes↗
PubMed1999

Results of the 1997 SENTRY Antimicrobial Surveillance Program in Three Brazilian Medical Centers.

The SENTRY Antimicrobial Surveillance Program began in January, 1997, and is designed to monitor nosocomial and selected community acquired infections via a worldwide surveillance network of sentinel hospitals distributed equally by geographic location and size. Three sites in Brazil - Rio de Janeiro, Florianópolis, and São Paulo - participated in the SENTRY Antimicrobial Surveillance Program stet. Rank order of occurrence and antimicrobial susceptibility of pathogenic species causing bloodstream infections, pneumonia, wound or skin and soft tissue infections, and urinary tract infections (UTI) in hospitalized patients were determined by collecting consecutive isolates over a specified period of time. Antimicrobial susceptibilities of Streptococcus pneumoniae, Haemophilus influenzae, and Moraxella catarrhalis obtained from outpatients with respiratory tract infections were also evaluated. The isolates for the evaluated infections were: 1) bloodstream - 20 consecutive isolates in each calendar month during a 12-month period; 2) pneumonia - 100 consecutive isolates over a 6 month period; 3) wound or skin and soft tissue - 50 consecutive isolates over a 3 month period; and 4) UTI - 50 consecutive isolates over a 3 month period. Each hospital also contributed, over a 6 month period, consecutive clinically significant outpatient isolates (one isolate per patient) of S. pneumoniae, H. influenzae, and M. catarrhalis that were considered pathogens in respiratory tract infections. Data collected for each isolate included species identification, antimicrobial susceptibility profile, date of isolation, and specimen type. Molecular studies were performed on selected isolates. A total of 1,241 bacterial strains were obtained; the majority were cultured from hospitalized patients, while 139 were fastidious organisms from community acquired respiratory tract infections. Gram-negative bacilli and S. aureus were the predominant pathogens, and Enterobacter spp. was a significant pathogen. The predominance of P. aeruginosa and Acinetobacter spp. and the significant levels of resistance to most agents are of major concern, as is the epidemic rate of ESBL-producing strains of Klebsiella spp. and E. coli in Brazil, which is much higher than rates seen in other areas of the world. Resistance among P. aeruginosa and the Enterobacteriaceae to fluoroquinolones, oxacillin-resistant S. aureus, and penicillin- and trimethoprim-sulfamethoxazole-resistant pneumococci were other significant resistance issues identified in this surveillance study. Vancomycin resistance among the enterococci, S. aureus, and S. pneumoniae was not identified. This benchmark study will serve as comparison for future surveillance studies, including the ongoing SENTRY program, to monitor emerging resistance trends in Brazil. The high rates of resistance observed in this study underscore the need for global surveillance and local action.

Journal Article↗
PubMed1990

Oral complications of cancer therapies. Surveillance cultures.

Surveillance cultures can be defined as an attempt to take microbiologic inventory, usually for bacteria and fungi, occasionally for viruses, at predetermined times during a patient's clinical course. They are useful in understanding the epidemiology of infection, evaluating techniques of infection prevention, assaying the effectiveness of preventive techniques, and guiding therapeutic decisions when empiric antimicrobial therapy is indicated. As such, they are most frequently used for patients at high risk of infection, such as those with acute leukemia receiving remission induction chemotherapy or bone marrow transplantation therapy. The sites sampled most frequently for surveillance cultures are the nose, oral cavity (pharynx or gingiva), and either the perianum or a stool specimen. Since hospital microbiology laboratories are not designed for the requirements of surveillance culturing, it is essential that such cultures only be obtained following appropriate communication and agreement with the laboratory directors.

Bacteria↗
PubMed2006

Potential confounding in evaluating infection-control interventions in hospital settings: changing antibiotic prescription.

The colonization dynamics of antibiotic-resistant pathogens in hospital settings are complex, with multiple and continuously interacting variables (e.g., introduction of resistance, infection-control practices, antibiotic use). Quantification of these variables is indispensable in the evaluation of intervention studies, because these variables represent potential confounders. In this article, the complexity of colonization dynamics is described. Through a systematic review, we identified studies that evaluated the modification of antibiotic prescription to reduce antibiotic resistance in intensive care units (n=19), and the extent of confounding-control was determined. Most studies evaluated antimicrobial restriction/substitution (n=12) or antibiotic rotation (n=4). Sixteen studies had a prospective cohort design (before-after), of which 12 were without a control group. Introduction of antibiotic resistance was determined in 10 studies. The relative importance of colonization routes and adherence to infection-control measures were not determined in any study. Therefore, it remains uncertain whether observed changes in the prevalence of antibiotic resistance after intervention were causally related to the intervention. Appropriate choices of study design, primary end point (colonization rates rather than infection rates) and statistical tests, determination of colonization routes, and control of potential confounders are needed to increase validity of intervention studies.

Anti-Bacterial Agents↗
PubMedDate not supplied

Seroprevalence of hepatitis C virus infection and evaluation of serum aminotransferase levels among haemodialysis patients in Izmir, Turkey.

The seroprevalence of hepatitis C virus (HCV) infection was investigated among haemodialysis (HD) patients. Mean serum aminotransferase levels were also compared over 3 months in HCV-seropositive patients with and without viraemia, as well as in HCV-seronegative HD patients and HCV-seropositive, non-uraemic, viraemic patients. Seroprevalence of HCV infection was 19% among the 437 HD patients tested. Of the 61 HD HCV-seropositive, hepatotoxic medication- and alcohol-free patients, 38 (62%) were found to be viraemic, using quantitative HCV-RNA, on at least one occasion. Mean serum aminotransferase levels were significantly higher in viraemic HD patients (compared with non-viraemic patients), suggesting that HCV-RNA positivity is an important predictor of increased enzyme activity in these patients. As expected, aminotransferase levels in HCV-seropositive HD patients tended to be lower than levels in HCV-seropositive non-uraemic patients.

Adult↗
PubMed1985

Respiratory infections: clinical evaluation.

A review of clinical studies of piperacillin shows that it is valuable for the treatment of respiratory infections due to Enterobacteriaceae, Pseudomonas sp, anaerobes, and mixed flora including anaerobes. Various studies of a total of 420 patients treated with piperacillin for lower respiratory tract infections found that 97% of the patients were cured or markedly improved. Piperacillin has also been found as effective as combination therapy (gentamicin or tobramycin plus carbenicillin or ticarcillin) in the treatment of serious infections, including pneumonia and several caused by gram-negative organisms and anaerobic organisms. A review of the literature on bacteriological responses to piperacillin shows that 126 of 153 (82%) of the susceptible strains could be eradicated. Streptococcus pneumoniae, beta-hemolytic streptococci, Haemophilus influenzae, Peptostreptococcus sp, Bacteroides sp, and Fusobacterium sp have been completely eradicated by treatment with piperacillin. Most of the published studies indicate that therapy with the drug is usually well tolerated.

Amikacin↗
PubMed1992

HIV-1 and HIV-2 infection in children in Abidjan, Côte d'Ivoire.

We conducted a study of 1,003 well and hospitalized children, birth to 5 years old, in Abidjan, Côte d'Ivoire, to determine the prevalence of HIV-1 and HIV-2 infection, evaluate risk factors for infection, and describe associated clinical characteristics. The overall seroprevalence was significantly higher for children in the hospital (10.8%) than for those attending the clinic (3.6%). HIV-1 was the predominant virus in both populations, comprising 87% (hospital) and 77% (clinic) of the seroreactive blood specimens. Ninety-two percent of seroreactive children of all ages had a mother who was HIV positive; 77% of seroreactive children greater than or equal to 15 months old had an HIV-infected mother. The remaining seropositive children had a history of receiving blood transfusions. Hospitalized children who were HIV-1 positive or dually seroreactive were more likely to have HIV-related clinical signs and symptoms than HIV-negative children. These findings suggest that HIV infection is an important cause of morbidity for children in Abidjan and that maternal infection is the primary risk factor for both HIV-1 and HIV-2 infection in children. Further evaluation and attention should be given to transmission, clinical characteristics, and the impact of HIV infection in children in West Africa, where both HIV-1 and HIV-2 are present.

Child, Preschool↗
PubMed1999

Mouse model of respiratory syncytial virus infection to evaluate antiviral activity in vivo.

In this study, we have developed a practical mouse model for evaluating in vivo the antiviral activity of compounds against respiratory syncytial virus (RSV) infection. BALB/c mice are not particularly susceptible to RSV infection; however, infection rates were improved by pretreatment with the immunosuppressive agent cyclophosphamide (CYP). When mice were inoculated intranasally with RSV A2 strain, the pulmonary RSV titres of CYP-pretreated 10-week-old mice were higher than those of untreated 10-week-old and 28-week-old mice, peaking on days 4 and 5 post-infection. Sections of lung from RSV-infected mice pretreated with CYP, taken on day 4 post-inoculation, showed widespread evidence of interstitial pneumonia and other significant pathological changes. We also confirmed that ribavirin, a representative antiviral agent, significantly reduced the pulmonary RSV titres of mice pretreated with CYP when administered intraperitoneally.

Animals↗
PubMed1980

An experimental model to determine the effects of adjuvant therapy on the incidence of postoperative wound infection: I. Evaluating preoperative radiation therapy.

This study investigated the effects of local preoperative radiation on the tissue resistance to surgical infection. Preoperative radiation was given to the skin of the backs of 144 rats in two doses and wounded at intervals after the radiation. As determined by quantitative bacterial counts of the wounds 4 days after wounding, 80 to 100 percent of the rats in each group healed their wounds with counts that were 10(3) organisms per gram, or less, in spite of the dose of radiation or the interval to wounding. In an additional 560 rats, 10(4) S. aureus organisms were inoculated into the surgical wounds made at various intervals after three doses of radiation. In this part of the study, the rates of infection (as determined by bacterial counts of 10(5) per gram or more) increased significantly with the increasing dose of radiation, as well as with the increasing interval from radiation to wounding. These data demonstrate that radiated tissue cannot tolerate bacterial contamination as well as normal tissue. Since surgery in the head and neck area results in the contamination of the wounds with saliva rich in virulent organisms, we propose that preoperative radiation be discontinued in favor of postoperative radiation.

Animals↗
PubMed1985

Results of bacteriophage treatment of suppurative bacterial infections. V. Evaluation of the results obtained in children.

The results of phage therapy applied in 114 cases of suppurative bacterial infections in children were analyzed. Positive therapeutic results were obtained in 109 (95.6%) cases. The results confirmed great effectiveness of bacteriophages in the treatment of septic infections, spontaneous or postoperative, caused by pyogenic Staphylococci, Klebsiella, Escherichia, Proteus and Pseudomonas bacteria.

Adolescent↗
PubMed2004

Relationship between bacterial infection and evaluation using a laser fluorescence device, DIAGNOdent.

The aim of this in vitro study was to investigate the relationship between bacterial infections in carious dentin when detected by two different methods -- polymerase chain reaction (PCR), and a laser fluorescence device, DIAGNOdent. Dentin was removed every 300 micro m in the direction of the pulp chamber in 10 extracted molars with occlusal dentin caries and 3 extracted sound molars. Dentin surfaces were evaluated using DIAGNOdent, and dentinal tissue samples were removed by using a round bur before and after each removal. Bacterial DNA in the dentinal tissues was detected by PCR, using primers based on the nucleotide sequence of a conserved region of the 16S rDNA, and yielded a PCR product of 466 bp. The rates of bacterial detection increased as the DIAGNOdent values increased. In the 10 specimens, the lowest DIAGNOdent value at which bacteria were detected was 15.6; at DIAGNOdent values below 15.6, no bacteria were detected. The results of a receiver operating characteristic (ROC) curve for the DIAGNOdent values showed that the area under the ROC curve was 0.91. This study clarified the relationship between the DIAGNOdent values of dentin caries and the rates of bacterial detection.

Area Under Curve↗
PubMed2002

Left ventricular dysfunction in children with fulminant enterovirus 71 infection: an evaluation of the clinical course.

We describe 2 children with typical hand, foot, and mouth disease due to enterovirus 71 infection, 1 of whom died. Both cases were complicated by acute fulminant shock syndrome; the patients had remarkable acute left ventricular dysfunction. The clinical experience indicates that the rapid death associated with fulminant enterovirus rhombencephalitis is the result of rapid cardiogenic shock rather than neurogenic pulmonary edema.

Child, Preschool↗
PubMed1985

Results of bacteriophage treatment of suppurative bacterial infections. IV. Evaluation of the results obtained in 370 cases.

The results of phage therapy applied in 370 cases of suppurative bacterial infections were analyzed. Positive therapeutic results were obtained in 342 (92.4%) cases. The results obtained confirmed the previous findings on great effectiveness of bacteriophages in the treatment of septic infections, spontaneous or postoperative, caused by pyogenic Staphylococci, Klebsiella, Escherichia, Proteus and Pseudomonas bacteria.

Adolescent↗
PubMed1995

A comparison of filtered leukocyte-reduced and cytomegalovirus (CMV) seronegative blood products for the prevention of transfusion-associated CMV infection after marrow transplant.

We performed a prospective, randomized trial in CMV seronegative marrow recipients to determine if filtered blood products were as effective as CMV-seronegative blood products for the prevention of transfusion-transmitted CMV infection after marrow transplant. Before transplant, 502 patients were randomized to receive either filtered or seronegative blood products. Patients were monitored for the development of CMV infection and tissue-documented CMV disease between days 21 and 100 after transplant. Infections occurring after day 21 from transplant were considered related to the transfusion of study blood products and, thus, were considered evaluable infections for the purpose of this trial. In the primary analysis of evaluable infections, there were no significant differences between the probability of CMV infection (1.3% v 2.4%, P = 1.00) or disease (0% v 2.4%, P = 1.00) between the seronegative and filtered arms, respectively, or probability of survival (P = .6). In a secondary analysis of all infections occurring from day 0 to 100 post-transplant, although the infection rates were similar, the probability of CMV disease in the filtered arm was greater (2.4% v 0% in the seronegative arm, P = .03). However, the disease rate was still within the prestudy clinically defined acceptable rate of < or = 5%. We conclude that filtration is an effective alternative to the use of seronegative blood products for prevention of transfusion-associated CMV infection in marrow transplant patients.

Adolescent↗